Threonine catabolism in Trypanosoma brucei

Area of Science:

• Biochemistry
• Parasitology
• Molecular Biology

Background:

• Trypanosoma brucei is a protozoan parasite causing human African trypanosomiasis.
• Understanding parasite metabolism is crucial for developing therapeutic strategies.
• L-threonine catabolism represents a potential metabolic target in trypanosomes.

Purpose of the Study:

• To elucidate the biochemical pathway of L-threonine catabolism in Trypanosoma brucei.
• To characterize the key enzymes involved in this metabolic process.
• To determine the presence and activity of this pathway in different life stages of the parasite.

Main Methods:

• Enzyme assays to measure L-threonine dehydrogenase and aminoacetone synthase activity.
• Biochemical analysis to determine enzyme molecular weights.
• Investigation of enzyme sensitivity to sulphydryl reagents.

Main Results:

• L-threonine is catabolized to glycine and acetate in equimolar amounts.
• The pathway involves L-threonine dehydrogenase (EC 1.1.1.103) and aminoacetone synthase (EC 2.3.1.29).
• The L-threonine dehydrogenase enzyme has a molecular weight of 28-38 kDa and is sensitive to sulphydryl reagents.

Conclusions:

• The identified pathway is active in both cultured and bloodstream forms of Trypanosoma brucei.
• The characterized L-threonine dehydrogenase is a key enzyme in this catabolic route.
• Enzyme properties suggest potential targets for antiparasitic drug development.